Is it fat, and not muscle?
Normally that's hormonal - different people lose fat in different areas first. If it is really fat, then burning fat will do away with it.
Another possibility is that they're what's known as "bitch tits". This comes from steroid use, hormonal imbalances, and overproduction of estrogen in the male body. The estrogen problem can be caused by an overabundance of testosterone in the body, as well (the body converts excess amounts of testosterone into estrogen).
Options:
#1 - Lose more weight
#2 - Try an estrogen blocker (nutritional supplement, not as scary as it sounds)
#3 - Try doing some more muscle balance and grow your ab region some